Objective: To determine whether combination antiretroviral therapy is associated with reduced detection of HIV-1 RNA and DNA in the anorectal mucosa of men who have sex with men (MSM).
Design: Cross-sectional study of 233 MSM recruited from community and clinic sites in Seattle, Washington between July 1996 and December 1997.
Methods: HIV-1 RNA and HIV-1 DNA were detected in anorectal swab specimens by polymerase chain reaction amplification assays.
Results: HIV-1 RNA was detected significantly less often in anorectal specimens from users of combination antiretroviral therapies, whether a protease inhibitor was received (15/89; 17%) or not (16/53; 30%), than in men not receiving therapy (43/88; 49%) (P < 0.001, P = 0.03, respectively). In contrast, HIV-1 DNA was detected only slightly less frequently in anorectal specimens obtained from men receiving protease inhibitors (35/81; 43%) or reverse transcriptase inhibitors alone (22/48; 46%) than in specimens from men not receiving therapy (45/78; 58%) (P = 0.07, P = 0.20, respectively). Among men with < 50 copies HIV-1 RNA/ml plasma, detection of HIV-1 RNA in anorectal specimens was rare (1/54; 2%) but detection of HIV-1 DNA was common (14/50; 28%).
Conclusions: Combination antiretroviral therapy is associated with reductions in HIV-1 RNA, but HIV-1 DNA remains detectable in the anorectal canal of almost half of MSM receiving such therapy. Condom use during anal intercourse should be encouraged, regardless of plasma viral load response to potent antiretroviral therapy.